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Can a normally open on/off pushbutton switch close without the button being pushed? Answered

Hi all,

I'm not an electrician, now it's said.

I'm building a device containing a small on/off (latching) switch. When the switch is pushed, the device is activated and remains active until the batteries run out. The device will only be activated once, and afterward it's discarded. This means that the switch will only be pressed once in its lifetime.

The use of the switch is to press the button to make the spring drive the contact point to rotate and close the circuit.

The device must not be unintededly activated as it could have severe consequences. The button is protected to prevent from this, but I need to know the probability that the switch itself closes, due to a failure.

The manufacturer (Chinese) just tells me "don't worry" so I need a second opinion. Is there a way to estimate the probability over a 3 year period? Because if there is a risk at all, I might need to add an extra switch to create a "double commando".

Thanks for your help.
/Karolina

Discussions

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iceng

1 year ago

Electric switches are made to respond to physical action to close an electric contact.

Some switches use a spring and detent..

A miniature switch may have an extremely short action..

Should the "No Worry Chinese" spring steel loose its temper it may alter the switch as an earthly quake or road rumble could also do..

Historically, I have handled 9,000 + switches in my career and never had a single one activate on it's own, while about ten that would not work (activate)..

I would be much more concerned about batteries staying ready fresh for three years..

Hope this helps some..

Though a picture would help :-)

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karolina81iceng

Answer 1 year ago

Yes, I also think that the spring is the weakest link here. If that would come loose inside, it could potentially close the circuit. BUT, the spring is locked from both top and bottom and can't really come loose unless it breaks in two. And that also seems very unrealistic...?

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iceng

1 year ago

Is the picture of a rotary action switch ?

How is it worked ? a single finger or finger and a thumb ?

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karolina81iceng

Answer 1 year ago

The switch has a small pushbutton and when it's pressed, the wheel rotates 45 degrees and closes the circuit. One single finger/thumb.